Process for breaking petroleum emulsions



Walenle Jlnly Ell, 1943 PRWDESS FUR BREAKING PETROLEUM EMULSIONS Melvin De Groote, University City, and Bernhard Keiser, Webster Groves, Mo., assignors to Petrolitc Corporation, Ltd, Wilmington, Del., a

corporation of Delaware No Drawing. Application .luly 7, lilil, Serial No. 401,373

(Cl. zsz-aii) iDlaims.

This invention relates primarily to the resolution of petroleum emulsions.

One object of our invention is to provide a novel process for resolving petroleum emulsions of the water-in-oil type, that are commonly referred to as cut oil, roily oil," emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

Another object is to provide an economical and rapid process for separating emulsions which have'been prepared under controlled conditions from mineral oil, such as crude petroleum and relatively soft waters or weak brines. Controlled emulsification and subsequent demulsification under the conditions just mentioned is of significant value in removing impurities, particularly inorganic salts, from pipeline oil.

The new chemical compound or composition of matter herein described, which is used as the demulsifier of our process, is exemplified by the acidic, or preferably, neutral ester derived by complete esterification of one mole of a polyalkylene glycol of the kind hereinafter described, with two' moles of a fractional ester derived from a hydroxylated material of the .kind herein described, and a polybasic carboxy acid having not over six carbon atoms.

If a hydroxylated material, indicated for the sake of convenience by the formula T.OH, is reacted with a polybasic carboxy acid, which, similarly, may conveniently be indicated as being of the dibasic type, by the formula HOOC.D.COOH, then the fractional ester obtained by reaction between equimolar quantities may be indicated by the following formula:

HOOC.D.COO.T

The polyethylene glycol may be characterized by materials of the kind such as heptaethylene glycol, octaethylene glycol, nonaethylene glycol, decaethylene glycol, to and including heptadecaethylene glycol. For convenience these polyethylene glycols may be indicated by the following formula:

OH (C2H40) mH in which m varies from 7 through 17.

Instead of polyethylene glycols, one may use polypropylene glycols or polybutylene glycols.

Thus, for convenience, in the broadest aspect,

the polyalkylene glycols employed may be indicated by the following formula:

OH(C12H211,0) 111K in which m has its previous significance, and n represents a numeral varying from 2 to 4.

Thus, the bulk of the materials herein contemplated may be indicated within certain variations, as hereinafter stated, by the neutral ester derived by esterification of one mole of a glycol of the kind above described, with two moles of a fractional ester of the kind previously described. The formation of the compound may be indicated by the following reaction, although obviously, it is immaterial what particular procedure is employed to produce the particular chemical compound or product:

As indicated previously, the polybasic acids employed are limited to the type having not more than six carbon atoms, for example, oxalic, malonic, succinic, glutaric, and adipic. Similarly, one may employ acids such as fumaric, maleic, glutaconic', and various others, including citric, malic, tartaric, and the like. The selection of the particular tribasic or dibasic acid employed is usually concerned largely with convenience of manufacture of the finished ester, and also of the price of the reactants. Generally speaking, the higher the temperature employed, the easier it is to obtain large yields of the esterified product. Although oxalic acid is compartively cheap, it decomposes somewhat readily at slightly above the boiling point of water. For this reason, it is more desirable to use an acid which is more resistant to pyrolysis. Similarly, when a polybasic acid is available in the form on an anhydride, such anhydride is apt to produce the ester with greater ease than the acid itself. For this reason, maleic anhydride is particularly adaptable; and also, everything else considered, the cost is comparatively low on a per molar basis, even though somewhat higher on a per pound basis. Succinic acid or the anhydride has many of the attractive qualities of maleic anhydride; and this is also true of adipic acid. For purposes of brevity, the bulk of the compounds hereinafter illustrated will refer to the use of maleic anhydride, although it is understood that any other suitable polybasic acid may be employed. Furthermore, for purposes of convenience, reference is made to the use of polyethylene glycols.

As has been previously indicated, such glycols can be replaced by suitable polypropylene or polybutylene compounds.

As far as the range of oxalkylated compounds employed as reactants is concerned, it is our preference to employ those having approximately 8-12 oxyalkylene groups, particularly 8-12 oxyethylene groups. The preference to use the oxyethylated compounds is due, largely, to the fact that they are commercially available, and particularly so in two desirable forms. The most desirable form is the so-called nonaethylene glycol, which, although consisting largely of nonaethylene glycol, may contain small amounts of heptaethylene and octaethylene glycols, and possibly minor percentages of the higher homologs. Such glycols represent the upper range of distillable glycols; and they may be conveniently referred to as upper distillable ethylene glycols. There is no particularly good procedure for making a sharper separation on a com- I mercial scale; and it is understood that mixtures of one or more of the glycols may be employed, as well as a single glycol. As pointed out, it is particularly preferred to employ nonaethylene glycol as commercially available, although it is understood that this product contains other homologs, as indicated.

Substantially as desirable as the upper distillable polyethylene glycols, are the lower non-distillable polyethylene glycol. These materials are available in the form of a waxy water-soluble material, and the general range may vary somewhat from decato tetradeca-ethylene glycol. As is well understood, the method of producing such glycols would cause some higher homologs to be formed; and thus, even in this instance, there may be present some oxyethylene glycols within the higher range above indicated. One need not point out that these particular compounds consist of mixtures, and that in some instances, particularly desirable esters, are obtanied by making mixtures of the liquid nonaethylene glycol with the soft, waxy, lower nondistillable pilyethylene glycols. For the sake of convenience reference in the examples will be to nonaethylene glycol; and calculations will be based on a theoretical molecular weight of 414. Actually, in manufacture the molecular weight of the glycol employed, whether a higher distillable polyethylene glycol or a lower non-distillable polyethylene glycol, or a mixture of the same should be determined and reaction conducted on the basis of such determination, particularly in conjunction with the hydroxyl or acetyl value.

It has been previously pointed out that it is immaterial how the compounds herein contemplated are manufactured,-although we have found it most desirable to react the selected glycol or mixtures of glycols with maleic anhydride in a ratio of two moles of the anhydride for one mole of the glycol. Under such circumstances. we have found little tendency to form longer chain polymers; and in fact, the product of reaction, if conducted at reasonably low temperatures, appears to be largely monomeric. For convenience, such intermediate product may then be considered as a dibasic or polybasic acid. One mole of the intermediate so obtained is then reacted with two moles of the alcoholic material of the kind subsequently described.

It is to be noted, however, that if one prepares a fractional acidic ester, then if two moles of the fractional acidic ester are reacted with one mole of the polyethylene glycol, there is no possibility for the formation of polymeric of esterification products under ordinary conditions.

The alcoholic bodies employed as reactants in one mode of manufacture of the present compounds are basic hydroxylated acylated polyamino compounds free from ether linkages. Such materials are described inter alia in U. S. Patent No. 2,243,329, dated May 27, 1941, to De Groote and Blair. For instance, this particular patent describes a basic type acylated polyamine of the following formula:

NCHHMCHHMNZLN/ in which n represents a small whole number varying from 2 to 10; :c is a small whole number varying from 1 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a higher molecular weight carboxy acid; RCO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and 73/00; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (1)) joint occurrence of an amido radical in which the acyl group is RC0 and a. hydroxyalkyl radical.

Needless to say, compounds of the kind therein described may be derived from polyamines having only two amino nitrogen atoms, as differentiatedfrom polyamines having 3 amino nitrogen atoms or more. Thus, in the above formula, a: may represent zero, as well as the numeral 1 to 10. It is obvious that numerous examples of the compounds indicated by the above formula are hydroxylatecl, due to the presence of one or more hydroxylated radicals of the following types:

(a) There may be present a hydroxyethyl group or a hydroxypropyl group or the like;

(b) The acyl group of the higher molecular weight carboxy acid may contain a hydroxyl group, as, for example, ricinoleie acid, hydroxystearic acid, etc.;

(o) The low molecular weight carboxy acid present may have a hydroxyl group in the acyl radical, such as would be the case when the radical is derived from lactic acid; and

(d) The amines above described may be considered as derivatives of dichloralkanes or alkylene dichlorides. This is discussed clearly in the aforementioned De Groote and Blair patent. If such amines, which are derivatives of propylene dichloride, as indicated by the following composition:

H H H c1c-c-cc1 H H H are, in turn, derived from glycerol dichlorhydrln (betahydroxy propylene dichloride) of the following composition:

it is obvious that another means is available for introducing an alcoholiform hydroxyl radical. Since this particular application or modification is extremely narrow in scope, and applies only to the instances where the alkylene group is a propylene radical, it is understood that in the hereto appended claims it is intended that wherever a propylene group is included, the hydroxy propylene group is considered as the functional equivalent, for the reasons stated.

Although in the compounds above described the radical RCO may be derived from a higher molecular weight carboxy acid, in the present instance the invention is concerned with the particular type, in which RC is derived from a more narrow class, to wit, detergent-forming unmodified detergent-forming acids, for instance,

instead of fatty acids, one might employ the chlorinated fatty acids. Instead of the resin acids, one might employ the hydrogenated resin acids. Instead of naphthenic acids, one might employ brominated naphthenic acids, etc.

The fatty acids are of the type commonly referred to as higher fatty acids; and of course this is also true in regard to derivatives of the kind indicated, insofar that such derivatives are obtained from higher fatty acids. The petroleum acids include not only naturally-occurring naphthenic acids, but also acids obtained by the xidation of wax, paraffin, etc. Such acids may have as many as 32 carbon atoms. For instance, see U. S. Patent No. 2,242,837, dated May 20, 1941, to Shields.

We have found that the new composition of matter herein described and employed as the demulsifier of our process, is preferably derived from unsaturated fatty acids having 18 carbon atoms. Such unsaturated fatty acids include the fatty acids, such as oleic acid, ricinoleic acid, linoleic acid, linolenic acid, etc. One may employ mixed fatty acids, as, for example, the fatty acids obtained from hydrolysis of cottonseed oil, soyabean oil, etc. Our preferred demulsifier is obtained from unsaturated fatty,

acids, and more especially, unsaturated fatty acids containing a hydroxyl radical, or unsaturated fatty acids, which have been subjected to an oxidation or oxyalkylation step, such as oxyethylation. Of the various unsaturated fatty acids, our choice is the hydroxylated type, to wit, ricinoleic acid.

For purposes of brevity, the bulk of any subsequent description will be concerned with fatty acids, and particularly unsaturated fattyacids. Further reference to other detergent-type monocarboxy acids is quite limited; but attention is directed to the fact that an adequate description is found in the aforementioned De Groote and Blair patent. The following examples are substantially as they appear in said patent. One must not forget, however, that in addition to the amines described in said patent as reactants, one can also use reagents such as ethylene diamine, bis (hydroxyethyl) ethylene diamine, tris (hydroxyethyl) ethylene diamine, etc. In view of what is said in the aforementioned De Groote and Blair patent, it will be obvious why the description of the amide is given as a primary raw material.

AMIDE EXAMPLE 1 283 parts of stearic acid amide are heated with 438 parts of triethylene tetramine for10 hours to about C. until a. test portion is soluble in diluted hydrochloric acid; at the end of the reaction the pressure is preferably lowered to about 15 mm.Hg. Thereby 380 parts of a product probably corresponding to the formula Ci'iI-b5C0.NH(CzH4NI-I)2C2H4NH2 (monostearyl triethylene tetramine) are obtained.

AMIDE EXAMPLE 2 281 parts of oleic acid amide yield with 584 parts of triethylene tetramine, when heated for. 10 hours to about 130 C., 400 parts of a product which is soluble in diluted hydrochloric acid, and probably corresponds to the mono-oleyl triethylene tetramine.

AMIDE EXAMPLE 3 283 parts of stearic acid amide are heated in the same way as described in Examples 1 and 2 with 400 parts of a mixture of polyalkylene polyamines obtainable by heating ethylene dichloride with ammonia under pressure and removing any ethylene diamin formed during the latter reaction. After distilling the excess of bases under reduced pressure, 430 parts of a paste are obtained which is soluble in diluted acids.

AMIDE EXAMPLE 4 300 parts of ricinoleic acid amide yield with 400 parts of a mixture of bases according to Example 3, when heated to about 8 hours to C., 450 parts of a mixture of acylated bases which is easily soluble in diluted acetic or hydrochloric acid.

- AMIDE EXAMPLE 5 From 300 parts of ricinoleic acid amide and 400 parts of a mixture of polyalkylene polyamines according to Examples 3 and 4, by heating for several hours to 150 0., simultaneously passing a current of dry air free from CO2, and finally removing the excess of bases partly by distilling under reduced pressure and partly by washing with water, there are obtained 430 parts of a mixture of polyalkylene polyamines which is acylated by the radical of ricinoleic acid.

AMIDE EXAMPLE 6 AMIDE EXAMPLE 7 310 parts by weight of the ethylester of oleic acid are heated with 286 parts by weight of triethylene tetramine at about 160 C. for 12 hours when a homogeneous solution is formed; the alcohol formed and the excess of triethylenetetramine are distilled off. The residual reaction product forms a brown oil, which is difficultly soluble in water and readily soluble .in alcohol,

benzene and dilute hydrochloric acid.

A quite similar product is obtainable by heating free oleic acid with an excess of methylene tetramine to about 180-200 C. and distilling oif the excess of triethylenetetramine under reduced pressure.

AMIDE EXAMPLE 8 200 parts by weight of olive oil are heated at 180-200 C. with 300 parts by weight of a. mixture of bases, which is obtained by the action of ammonia on ethylene chloride at 80-120" C. under pressure of atm. and after distilling of! the ethylene diamine said mixture of bases boiling at about mm. mercury between 90 and 300 C. When a test portion of the reaction product is smoothly soluble in dilute hydrochloric acid, the vtater formed and the excess bases are distilled ofi under reduced pressure and a yellowish brown 011 is obtained, a solution of which in dilute hydrochloric acid can be used as a washing or wetting agent.

AMIDE EXAMPLE 9 350 grams of monostearin and 300 grams of triethylenetetramine are heated together at 180 200 C. for 3 to 4 hours and then the displaced glycerine and th excess triethylenetetramine' were washed out with water and the resulting product dried.

AMIDE EXAMPLE 10 In the prior examples tetraethylene pentamine is substituted for the amines employed in the prior examples by using a suitable molecular equivalent, but without increasing the amount of fatty acid compound employed.

AMIDE EXAMPLE 11 Purified naphthenic acids derived from Gulf Coast crudes are employed in various examples preceding.

AMIDE EXAMPLE 12 Carboxy acids derived from oxides of Pennsylvania crude oil and having approximately 10-14 carbon atoms'per mole of fatty acid, are substituted in the previous examples.

BAsIc TYPE OXYALKYLATION COMPOUND OF AMIDO DERIVATIVE or POLYAMINE.Intermediate EE- ample 1 Materials of the kind described in Amide examples, Nos. 1-12, preceding, are treated with one mole of ethylene oxide in the manner previously described, so as to introduce one oxyethyl radical.

BAsIc TYPE OXYALKYLATION COMPOUND 0F AMIDO DERIVATIVE or PoLYAMINE.Intermediate Ea:- ample 2 The same procedure is followed as in the preceding example, except that more than one oxyalkyl group, or rather, Oxyethyl group, is introduced, the preference being to introduce two or three hydroxyethyl groups.

BAsIc TYPE OXYALKYLATION COMPOUND or AMIDO DERIVATIVE or POLYAMINE.--Intermediate Ea:- ample 3 Propylene oxide is substituted for ethylene oxide in Examples 1 and 2, preceding.

BAsIc TYPE OXYALKYLATION COMPOUND 0F AMIDO DERIVATIVE OP POLYAMINE.I7ZteTmediate Ea:- ample 4 Glycid is substituted for ethylene oxide in Examples 1 and 2, preceding.

OXYALKYLATION DERIVATIVES OF POLYAMINE Example 1 Suitable quantities of diethylene triamine are treated with ethylene oxide in various amounts, so as to introduce 1, 2 and 3 hydroxyethyl groups. The temperature employed is approximately -240, and the catalyst is preferably sodium methylate in amounts varying from /2% to /z%.

OXYALKYLATION DERIVATIVES OP POLYAMINE Example 2 Triethylene tetramine is substituted for diethylene triamine in Example 1.

OXYALKYLATION DERIVATIVES or POLYAMINE Example 3 Tetraethylene pentamine is substituted for diethylene triamine in Example 1.

OxYALxYLATION DERIVATIVES OF POLYAMINE Example 4 Pentaethylene hexamine is substituted for diethylene triamine in Example 1.

BAsIc TYPE ACYLATION DERIVATIVE 0F OxYAL- KYLATED PoLYAMINE.Intermediate Example 5 A material if the kind described in Oxyalkylation derivatives of polyamine, Example 1, is acylated in the same manner in which amides are obtained in Amide Examples 1-12, previously described.

BAsIO TYPE ACYLATION DERIVATIVE OF OXYAL- KYLATED PoLYAMINE.Inte1-mediate Example 6 A material of the kind described in Oxyalkylation derivatives of polyamine, Example 2, is acylated in the same manner in which amides are obtained in Amide Examples 1-12, previously described.

BAsIc TYPE ACYLATION DERIVATIVE OP OXYAL- KYLATED POLYAMINE.-Iniermediate Example 7 A material of the kind described in Oxyalkylation derivatives of polyamine, Example 3, is acylated in the same manner in which amides are obtained in Amide Examples 1-12, previously described.

BAsrc TYPE ACYLATION DERIVATIVE or OxYAL- KYLATED PoLYAMmE.Intermediate Example 8 A material of the kind described in Oxyalkylation derivatives of polyamine, Example 4, is acylated in the same manner in which amides are obtained in Amide Examples 1-12, previously described.

BAsIc TYPE RE-AcYLATED OXYALKYLATION Com- POUND or AMIDO DERIVATIVE 0F POLYAMINE. Intermediate Example 9 the re-acylation, or second acylation, of materials of the kind exemplified by Intermediates 1-4, inclusive, and particularly when such reacylation takes place by means of detergentforming acids, which, in the preferred form, are illustrated by fatty acids, and more particularly, by the hydroxylated fatty acid type. The preferred member of this type, in the present instance, as in other instances, is ricinoleic acid.

Having obtained basic hydroxylated polyamino compounds of the kind previously described, the next step is to obtain fractional esters derived from nonaethylene glycol of the kind described in the earlier part of the present disclosure. Such materials may be illustrated by the following examples:

GLYCOI. ESTER INTERMEDIATE PRODUCT Example 1 One pound mole of nonaethylene glycol is treated with two pound moles of maleic anhydride, so as to form nonaethylene glycol dihydrogen dimaleate.

GLYCOL ESTER INTERMEDIATE PRODUCT Example 2 A mixture of lower non-distillable polyethylene glycols, representing approximately decato tetradecaethylene glycol, is substituted for nonaethylene glycol in the preceding example.

GLYCOL ESTER INTERMEDIATE PRODUCT Example 3 .A 50-50 mixture of nonaethylene glycol and lower nondistillable polyethyeene glycols of the kind described in the previous example is substituted for nonaethylene glycol in Example 1.

GLYCOL ESTER INTERMEDIATE PRODUCT Example 4 Adipic acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYCOL EsTER INTERMEDIATE PRODUCT Example 5 Oxalic acid is substituted for maleic anhydri'de in Examples 1-3, preceding.

GLYCOL ESTER INTERMEDIATE PRODUCT Example 6 Citric acid is substituted for maleic anhydride in Examples 1-3, preceding.

GLYCOI. ESTER INTERMEDIATE PRODUCT Example 7 Succinic anhydride is substituted for maleic anhydride in Examples 1-3, preceding. The method of producing such fractional esters is well known. The general procedure is to employ a temperature above the boiling point of water and below the pyrolytic point of the re- Sometimes esterification is conducted most readily in the presence of an inert solvent that carries away the Water of esterification which may be formed, although, as is readily appreciated, such water of esterification is absent when tne reaction involves an acid anhydride, such as maleic anhydride, and a glycol. However, if water is formed, for instance, when citric acid is employed, then a solvent such as xylene may be present and employed to carry Off the Water formed. The mixture of xylene vapors and water vapors can be condensed so that the water is separated. The xylene is then returned to the reaction vessel for further circulation. This is a conventional and well-known procedure and requires no further elaboration.

COMPOSITION OF MATTER Example 1 COMPOSITION OF MATTER Example 2 Basic type oxyalkylation compound of amido derivative of polyamine, Intermediate Example 2, is substituted for Basic type oxyalkylation compound of amido derivatives of polyamine, Intermediate Example 1, in the example precedine. I

COMPOSITION OF MATTER Example 3 Glycol ester intermediate products of the kind exemplified by Glycol ester intermediate products, Examples 4-7, preceding, are substituted for the products of the kind exemplified in Glycol ester intermediate products, Examples 1, 2 and 3, preceding, in the previous two examples.

It is to be noted that this second step is an esterification reaction, and the same procedure is employed as suggested above in the preparation of the intermediate product. Needless to say, any particular method may be used to produce the desired compounds of the kind indicated. In some instances it may be' desirable to conduct the esterification reaction in the presence of a non-volatile inert solvent which simply acts as a diluent or viscosity reducer.

In the preceding examples, attention has been directed primarily to the monomeric form, or at least, to the form in which the bifunctional alcohol, i. e., a glycol, and the polyfunctional acid, usually a bifunctional compound, react to give a chain type compound, in which the adjacent acid and glycol nucleus occur as a structural unit. For instance, in the monomeric form this may be indicated in the following manner:

acid glycol acid If, however, one prepared an intermediate product employing the ratio of three moles of maleic anhydride and two moles of nonaethylene glycol, the tendency would be to produce a prodnot which might be indicated in the following manner:

acid glycol acid glycol acid Similarly, three moles of the glycol and four moles of the acid might tend to give a combination which may be indicated thus:

acid glycol acid glycol acid glycol acid Another way of stating the matter is that the composition may be indicated in the following manner:

in which the characters have their previous significance and a: is a relatively small whole number less than 10, and probably less than and in the monomeric form :r, of course, is l. The limitations on the sizeof a: are probably influenced largely by the fact that reaction leading to further growth is dependent upon random contact.

Some of the products are self-emulsifiable oils, or self-emulsifiable compounds; whereas, others give cloudy solutions or sols; and the most desirable type is characterized by giving a clear solution in water, and usually in the presence of soluble calcium or magnesium salts, and frequently, in the presence of significant amounts of either acids or alkalies.

Water solubility can be enhanced in a number of ways which have been suggested by previous manufacturing directions, for instance:

(a) By using a more highly polymerized ethylene glycol;

(b) By using a polymeric form instead of a monomeric form in regard to the unit which forms the chain between the two alcoholic nuclei;

(o) By using a polybasic carboxy acid of lower molecular weight, for instance, maleic acid, instead of adipic acid; and

((1) By using an amino body having fewer high molal acyl groups, or more amino nitrogen atoms, or any other obvious variant.

Indeed, in many instances the acylated polyamino compound is water-soluble prior to reaction with the glycol ester. It is to be noted that in this instance one is not limited to bydroxylated materials which are water-insoluble prior to reaction with a glycol ester; but they may, in fact, be perfectly water-soluble.

Actually, a reaction involving an alcohol and an acid (esterification) may permit small amounts of either one or both of the reactants, depending upon the prede ermined proportion, to remain in. an unreacted state. In the actual preparation of compositions of the kind herein contemplated, any residual acidity can be removed by any suitable base, for instance, ammonia, triethanolamine, or the like, especially in dilute solution. Naturally, precaution should be taken, so that neutralization takes place without saponification or decomposition of the ester. In some cases there is no objection to the presence of the acidic group. Indeed, if a tribasic acid be employed in such a manner as to leave one free carboxyl group, then it is usually desirable to neutralize such group by means of a suitable basic material.

In the hereto appended claims, reference to a neutral product refers to one in which free carboxylic radicals are absent. I

Conventional ,demulsifying agents employed in the treatment of oil field emulsions are used mulsifier is usedin connection with acidification;

as such, or after dilution with any suitable solvent, such as water; petroleum hydrocarbons, such as gasoline, kerosene, stove oil, a coal tar product, such as benzene, toluene, xylene, tar acid oil, cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may be employed as diluents. Miscellaneous solvents, such as pine oil, carbon tetra-, chloride, sulfur dioxide extract obtained in the refining of petroleum, etc., may be employed as diluents. Similarly, the material or materials herein described may be admixed with one or more of the solvents customarily used in connection with conventional demulsiiying agents, provided that such compounds are compatible. They will be compatible with the hydrophile type of solvent in all instances. Moreover, said material or materials may be used alone, or in admixture with other suitable well known classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water solubility. Sometimes they may be used in a form which exhibits relatively limited oil solubility. However, since such reagents are sometimes used in a ratio of 1 to 10,000, or 1 to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the concentration employed. This same fact is true in regard to the material or materials herein described, except that they are invariably water-soluble.

We desire to point out that the superiority of the reagent or demulsifying agent contemplated in our herein described process for breaking petroleum emulsions, is based upon its ability to treat certain emulsions more advantageously and at a somewhat lower cost than is possible with other available demulsifiers, or conventional mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein delscribed will find comparatively limited applicaltion, so far as the majority of oil field emulsions are concerned; but we have found that such a demulsifying agent has commercial value, as it will economically break or resolve oil field emulsions in a number of cases which cannot be treated as easily or at so low a cost with the demulsifying agents heretofore available.

In practising our improved process for resolving petroleum emulsions of the water-in-oil type, a treating agent or demulsifying agent of the kind above described is brought into contact with or caused to act upon the emulsion to be treated, in any of the various ways, or by any of the various apparatus now generally used to resolve or break petroleum emulsions with a chemical reagent, the above procedure being used either alone, orin combination with other demulsifying procedure, such as the electrical dehydration process.

The demulsifier herein contemplated may be employed in connection with what is commonly known as down-the-hole procedure, i. e., bringing the demulsifier in contact with thefluids of the well at the bottom of the well, or at some point prior to their emergence. This particular type of application is decidedly feasible when the de 0f calcareous oil-bearing strata, especiallyif suspended in or dissolved in the acid employed for acidification.

It will be apparent to those skilled in the art that residual carboxyl acidity can be eliminated by est-erification with a low molal alcohol, for instance, ethyl, methyl, or propyl alcohol, by conventional procedure, so as to give a substantially neutral product. The introduction of such low molal hydrophobe groups does not seriously affect the solubility, and in some instances, gives increased resistance, to soluble calcium and magnesium salts, for such property is of particular value. Usually, however, neutralization with a dilute solution of ammonia or the like, is just as practicable and less expensive.

In the hereto appended claims it is intended that the monomeric forms contemplate also the polymeric forms, insofar that the polymeric forms are nothing more or less than a repetition of the monomeric forms several times over, with the loss of one or more moles or water.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

l. A process for breaking petroleum emulsions of the water-in-oil type, characterized by sub-- jecting the emulsion to the action of a demulsifying agent comprising a water-soluble esterification product, derived by reaction between one mole of a polybasic compound and two moles of a basic hydroxylated acylated polyamino compound free from ether linkages; the polybasic compound being the esterification product of (A) a polyalkylene glycol having at least 7 and not more than 1'7 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for eachmole of the glycol; and said basic hydroxylated acylated polyamino compound free from ether linkages being of the following formula:

NCHZn(CnHZn in which n represents a small whole number varying from 2 to 10; :c is a small whole number varying from to Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; R'CO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and RCO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (12) joint occurrence of an amino radical in which the acyl group is RC0 and a hydroxyalkyl radical.

2. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a polybasic compound and two moles of a basic hydroxylated acylated polyamino compound free from ether linkages; the

polybasic compound being the esterification product of (A) a polyalkylene glycol having at least '7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms, and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and th ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for each mole of the glycol; and said basic hydroxylated acylated polyamino compound free from ether linkages being of the following formula:

in which n represents a small whole number varying from 2 to 10; :1: is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, RCO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboXy acid; R'CO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and RCO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical.

3. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a dibasic acid and two moles of a basic hydroxylated acylated polyamino compound free from ether linkages; the dibasic compound being the esterification product of (A) a polyalkylene glycol having at least 7 and not,

more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 6 carbon atoms; and (B) a dibasic carboxy acid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the dibasic acid for each mole of the glycol; and said basic hydroxylated acylated polyamino compound free from ether linkages being of the following type:

Ncnnmcnmmzim alkylene, in which instance the acyl group is a member of the class consisting of RC0 and R'CO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical.

4. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a dibasic acid and two moles of a hydroxylated acylated polyamino compound free from ether linkages; the dibasic compound being the esterification product of (A) a polyalkylene glycol having at least '7 and not more than 17 ether linkages, and the alkylene radical thereof containing at least 2 and not more than 4 carbon atoms; and (B) a polybasic carboxy acid having not more than 6 carbon atoms; and the ratio of the est-erifying reactants being within the range of more than 1 and not over 2 moles of the polybasic acid for, each mole of the glycol; and said basic hydroxylated acylated polyamino compound free from ether linkages being of the following type:

in which ll represents a small whole number varying from 2 to 10; a: is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; R'CO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of R00 and R'CO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (1)) joint occurrence of an amino radical in which the acyl group is RC0 and a hydroxyalkyl radical.

5. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble esterification product, derived by reaction between one mole of a dibasic acid and two moles of a hydroxylated acylated polyamino compound free from ether linkages; the dibasic compound bein the esterification product of (A) a polyethylene glycol having at least '7 and not more than 17 ether linkages; and (B) a dibasic carboxyacid having not more than 6 carbon atoms; and the ratio of the esterifying reactants being within the range of more than 1 and not over 2 moles of the dibasic acid for each mole of the glycol; and said basic hydroxylated acylated polyamino compound free from ether linkages being of the following type:

NCnH2n(C..H2nNZ)1N in which n represents a small whole number varying from 2 to 10; m-is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; RCO is 76 an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D i a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and R'CO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (1)) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical.

6. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a, neutral, water-soluble chemical compound of the following formula type:

in which '1' is a radical derived by the dehydroxylation of a hydroxylated acylated polyamino compound free from ether linkages of the following type:

NC,.H;,.(C,.Hz..NZ),N

in which n represents a small whole number varying from 2 to 10; :c is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; R'CO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and R'CO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (22) joint occurrence of an amide radical in which the acyl group is RC0 and a hydroxyalkyl radical; OOC.D.COO is the acid in which T is a radical derived by the dehydroxylation of a hydroxylated acylated polyamino compound free from ether linkages of the following type:

in which n represents a small whole number varying from 2 to 10; a: is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; R'CO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalacyloxyalkylene radical in which the acyl group is RC; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical; OOC.D.COO is the acid radical derived from a dibasic acid by removal of the acidic hydrogen atoms; said acid radical having not over 6 carbon atoms; and m represents a numeral varying from 7 to 12.

8. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of the following formula type:

TOOC.D.COO (021-140) C2H4OOC.D.COO.T

in which T is a radical derived by the dehydroxylation of a hydroxylated acylated polyamino compound free from ether linkages of the following type:

in which n represents a small whole number varying from 2 to 10; :r is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, R'CO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; RCO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms or less: and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and R'COrand the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxvalkylene radical in which the acyl group is RC0; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical; 0OC.D.CO0 is the acid radical derived from malelc acid by removal of the acidic hydrogen atoms; and m represents a numeral varying from '7 to 12.

9. A' process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of the following formula type:

TOOC.D.COO (C2H4O) mC2HiOOC.D.COOiT in which T is a radical derived by the dehydroxylation of a hydroxylated acylated polyamino compound free from ether linkages 0f the following type:

I NCnIhACnHm-NZLN in which n represents a small whole number varying from 2 to 10; a: is a small whole number varying from 0 to 10; Z is a member of the class consisting of H, RCO, RCO, and D, in which RCO represents an acyl radical derived from a detergent-forming monocarboxy acid; RCO is an acyl radical derived from a lower molecular weight carboxy acid having 6 carbon atoms orless; and D is a member of the class consisting of alkyl, hydroxyalkyl, aminoalkyl, and acyloxyalkylene, in which instance the acyl group is a member of the class consisting of RC0 and R'CO; and the acylated polyamine is further characterized by the fact that there must be present a member of the class consisting of (a) acyloxyalkylene radical in which the acyl group is RC0; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical; OOC.D.COO is the acid radical derived from succinic acid by removal of the acidic hydrogen atoms; and m represents a numeral varying from 7 to 12.

10. A process for breaking petroleum emulsions of the water-in-oil type, characterized by subjecting the emulsion to the action of a demulsifying agent comprising a neutral, water-soluble chemical compound of the following formula type:

TOOC.D.COO(C2H4O) mC2H4OOC.D.COO.T

in which T is a radical derived by the dehydroxylation of a hydroxylated acylated compound free from other linkages of the following type: 40 z z NC,.Hz,.(C,.H2,.NZ),N

in which n represents a small whole number RC0 and R'CO; and the. acylated polyamine isfurther characterized by the fact that there must .be present a member of the class consisting of '(a) acyloxyalkylene radical in which the acyl 3 group is RC0; and (b) joint occurrence of an amido radical in which the acyl group is RC0 and a hydroxyalkyl radical; O0C.D.COO is the acid radical derived from adipic acid by removal of the acidic hydrogen atoms; and m represents a numeral varying from 7 to 12.

MELVINDE GROO IE. BERNHARD EISER. 

